In recent years, as a smart TV, a smart TV has been developed to which not only a function to display a TV broadcast video obtained by receiving a broadcast wave but also a variety of functions are added. For example, a smart TV has been developed in which a platform such as Android® is installed and which displays an image obtained by executing an application as a smartphone or a tablet personal computer (PC).
In addition, in recent years, a technique for meeting needs that users desire to view and listen to a TV broadcast video during execution of an application has been developed.
For example, PTL 1 discloses a TV conference device by which during a TV conference, an image of another site and images of shared materials may simultaneously be viewed on the same screen. In this TV conference device, a display unit is divided into a conference application display region and a material sharing display region, a TV conference screen is displayed in the conference application display region, and a material screen is displayed in the material sharing display region.
Further, PTL 2 discloses a technique in which a set top box (also referred to as STB) in which an OS is installed is used in order to add a function like a smart TV to a usual TV and an application executed by the STB and a TV broadcast video are simultaneously viewed and listened to. In this technique, a picture in picture (PinP) function of a TV is used to display an image of the application executed by the STB in a main screen and to display the TV broadcast video in a sub-screen.